用于图像压缩的小波变换编码

提出了一种二维小波变换编码方案，使用塔形算法结构将图像沿水平与垂直方向分解成一组多分辨率子图像。根据小波系数的统计特性和人类视觉特性，对小波系数进行门限量化，推导了量化门限与量化间隔的计算公式，量化后的多分辨率子图像采用自适应分块编码进一步进行压缩。计算机模拟结果证明了本方案的优越性能。     

冷轧钢带表面缺陷在线检测及系统的计算机接口

讨论了一种冷轧钢带表面缺陷在线检测系统的基本组成和原理，该系统能测量钢带的宽度，检测边裂、孔洞和重皮等缺陷。研究了采用存储器地址映像技术和双体ＲＡＭ总线切换技术设计的计算机接口，该接口能使数据的计算机输入和处理并行工作，省去了数据输入占用ＣＰＵ的时间，解决了实时检测系统高速数据的计算机输入和处理存在的时间冲突的难题。     

History of trace gases in presolar diamonds inferred from ion-implantation experiments

Diamond grains are the most abundant presolar grains found in primitive meteorites. They formed before the Solar System, and therefore provide a record of nuclear and chemical processes in stars and in the interstellar medium. Their origins are inferred from the unusual isotopic compositions of trace elements-mainly xenon-which suggest that they came from supernovae. But the exact nature of the sources has been enigmatic, as has the method by which noble gases were incorporated into the grains. One observation is that different isotopic components are released at different temperatures when the grains are heated, and it has been suggested that these components have different origins. Here we report results of a laboratory study that shows that ion implantation (previously suggested on other grounds) is a viable mechanism for trapping noble gases. Moreover, we find that ion implantation of a single isotopic composition can produce both low- and high-temperature release peaks from the same grains. We conclude that both isotopically normal and anomalous gases may have been implanted by multiple events separated in space and/or time, with thermal processing producing an apparent enrichment of the anomalous component in the high-temperature release peak. The previous assumption that the low- and high-temperature components were not correlated may therefore have led to an overestimate of the abundance of anomalous argon and krypton, while obscuring an enhancement of the light-in addition to the heavy-krypton isotopes.     

Valproic acid attenuates inflammation in experimental autoimmune neuritis

Valproic acid (VPA) is a short-chain branched fatty with anti-inflammatory, neuro-protective and axon-remodeling effects. We investigated the effects of VPA in rats in which experimental autoimmune neuritis (EAN) had been induced (EAN rats). VPA (300 mg/kg, intraperitoneally) administration to EAN rats once daily immediately following immunization significantly suppressed mRNA levels of interferon-γ, tumor necrosis factor-α, interleukin (IL)-1β, IL-4, IL-6 and IL-17 in the lymph nodes of EAN rats. In peripheral blood and sciatic nerves of EAN rats, Foxp3⁺ cells were increased but IL-17⁺ cells were decreased during VPA treatment. Furthermore, suppressive and therapeutic treatment with VPA greatly attenuated both accumulation of macrophages, T cells and B cells, and demyelination in sciatic nerves, and greatly reduced the severity and duration of EAN. In summary, our data demonstrated that VPA could effectively suppress inflammation in EAN, suggesting that VPA could be a potent candidate for treatment of autoimmune neuropathies.     

Zv上（y，k，k-1）-不相交差族的构造方法

给出了不相交差族的3种新构造方法：利用循环的B（k，1；v）（即CB（k，1；v））；利用循环的GDD及半循环的frame；当p≡5（mod12）为素数时，Z5p上的（5p，3，2）-DDF有一种特殊的构造方法．并得到了参数为（v，3，2）和（v，4，3）的不相交差族的一些新结果．     

传统中医在西方世界的传播:试释这一奇特现象

摘要从公元前一、二世纪的西汉时期开始,中国运用阴阳、五行等思想解释健康和疾病,建立了一个有效的、“科学”的治疗和预防疾病的医学体系,在中国运用与发展了两千多年,这就是“中国传统医学(CTM)”。20世纪50年代至70年代之间,中国医家对中医按科学和理性精神进行了整理、消化和吸收,使之切合于当代医学知识体系,这就是我们现在理解的“传统中医(TCM)”。中医在16世纪就为西方有所了解,尤其是针灸,18、19世纪之交在欧洲曾风靡一时。但接着在一个多世纪的时间里,由于现代生物、化学、医学的兴起,中医在西方受到了冷落。到了20世纪70年代,情况又发生了变化,传统中医再次在欧洲和美国大受欢迎。造成这一现象的根本原因不在于传统中医在临床上的效果,而是在于西方工业化国家中产生了一种宽泛的思潮,即对不加区分地用现代科学技术改变人类生活、开发自然所带来的危险的意识越来越强烈。在这种危机感下,西方人迫切需要一种对人体改变不大,对环境破坏较小,强调人与自然和谐共存的医学体系来补充或取代西方现有的生化医学。传统中医,特别是针灸,在西方得以流行,就是得益于这种对科学技术造福人类、不断进步的观点表示怀疑,对现代科技对环境的破坏表示忧虑的危机感。文章主要是通过对欧洲的环境主义和对科学技术的怀疑主义的背景分析,解释为什么“传统中医”能在这一思想大趋势中进入到西方社会。同时在另一方面,由于“传统中医”是对“中国传统医学”科学的、理性的整理和吸收,这使得它比较容易为强调科学和理性的西方文化所接受。“传统中医”当今在西方受到欢迎,这一奇特现象当从以上两方面进行解释。     

Lower receptor avidity required for thymic clonal deletion than for effector T-cell function.

Clonal deletion in the thymus plays a major part in T-cell tolerance to self antigens. But the mechanism of negative selection, its fine specificity and the threshold of affinity and avidity remains unknown. We have now examined these aspects of negative selection with mice expressing a transgenic T-cell receptor with specificity for lymphocytic choriomeningitis virus (LCMV) glycoprotein in association with the class I H-2Db molecule. These mice were rendered tolerant to LCMV by neonatal infection with mutant LCMVs bearing point mutations in the T-cell epitope recognized by the transgenic T-cell receptor. Variant LCMVs were also tested for their ability to elicit antiviral responses in transgenic mice in vivo and in vitro. Comparison in vivo revealed that a low-avidity receptor interaction, which was unable to induce effector T cells in the periphery, was still sufficient for clonal deletion in the thymus.     

Cell-mediated immunity in the liver of mice vaccinated against malaria.

Mice can be protected against several species of lethal malaria infection by vaccination, and their recovery correlates well with increased anti-malarial antibody levels, particularly IgG (ref.2). However, there is also a good correlation between protection by vaccines and priming for delayed-type hypersensitivity in the skin, although there is no obvious explanation for this effect. We now report an apparent relationship between protection and a cell-mediated immune response involving the migration of various types of cell capable of killing malaria parasites in vitro to the liver. We suggest that the effect of vaccination is to bring together parasites, specific antibody and nonspecific cytotoxic cells, and that the liver may be a major site for their interaction.